The present invention relates in general to the field of agriculture and the processing of harvested crops.
Vehicles designed to pick up and process crops—in particular self-propelled agricultural harvesting machines—are used for this purpose. The self-propelled agricultural harvesting machines are typically combine harvesters, forage harvesters, and all types of lifters that are operated to cut and/or gather crop material. Such machines typically can process the crop material in a known manner after cutting and/or gathering. One example will be described with reference to a combine harvester. In a combine harvester, cut ears of the crop material are conveyed into the interior of the machine, where the grain is separated from the rest of the biological crop material in a threshing and cleaning process. The resulting cleaned grain is conveyed to a grain tank in the combine harvester, while short parts of straw, chaff, tailings, husks, dust, etc. are returned to the field. However, not all of the grains are threshed out entirely from the ears of the crop material in the threshing process, and so a combine harvester comprises—in a known manner—a forward grain path and a return path, i.e. a mechanical return path, via which incompletely threshed ears are returned to the threshing process to be threshed again.
The setting of the working assemblies in the combining process is therefore particularly significant. If the setting for the threshing mechanism is too acute, the portion of damaged grain becomes too great, which is undesirable. If the setting is too gentle, grains that have not been fully threshed enter the crop material, which interferes with the further processing thereof. Husks and short straw that enter the crop material flow during threshing may be removed in a separating unit located downstream of the threshing stage, although a setting of the separating unit that is too acute may also result in grain losses. It is therefore very important to the land manager to collect high-quality crop material in the grain tank, and to avoid crop material losses in order to maintain a desired level of quality. Due to cross compliance and other quality parameters, the requirements on product safety are increasing in the production of foodstuff, and fodder. Consistent product safety can be ensured only if the composition of the crop material in the grain tank is detected and determined e.g. relative to the trimmings contained in the grain tank (miscellaneous impurities, extraneous seeds, damaged grain, shrivelled grains, chaff, etc.). The detection and determination of the quality of crop material in the grain tank is therefore particularly significant.
The invention therefore relates to a device for detecting and determining the composition of bulk material, in particular crop material, seeds, or other pourable agricultural products, which enables a qualified determination to be made—during transfer to the grain tank of agricultural harvesting machines, in particular self-propelled harvesting machines—regarding the composition of the crop material during the processing of the crop material, in order to thereby change or optimize the parameter settings of the working assemblies of an agricultural harvesting machine during the processing of the crop material, to ensure that the quality of the crop material after harvesting and processing is always optimal, and to thereby meet the increased quality requirements.
The quality of the crop material must be determined in order to continuously optimize the working assemblies to ensure the desired level of quality of the grain tank contents. Optimization means that the adjustment parameters of the working assemblies, or the combine harvester settings, can be changed as needed on the basis of the analysis of the crop material flow.
A device known from the prior art, which monitors the contents of the grain tank during combining and can change the adjustment parameters for the threshing units is known from EP 1 763 988 A1.
Document EP 1 763 988 A1 discloses a combine harvester which comprises an image detector at a position along the crop-material conveyance path, which is at the outlet of the grain elevator in this case, i.e. at the transition to the grain tank. The image detector is used to record images of the crop material flowing out of the grain elevator. A CCD camera is used as the image detector. The quality of the crop material flow is checked by reference to said images. The crop material flow is inspected for impurities such as remaining straw pieces, husks, non-threshed ears, etc., and portions of damaged grain. The images of the crop material flow recorded by the camera can be shown via a control unit in a display located in the driver's cab, thereby enabling the operator or driver to influence the adjustment parameters of the threshing units or to make changes thereto. The control unit also contains a series of reference images which can be used for comparison with the recorded images in order to identify any deviations in the images recorded in the combining process from the reference images, and to enable quality to be assessed relative to the reference images. This method of determining the quality of crop material has been thoroughly confirmed.
However, one disadvantage thereof is that grain, damaged grain, and non-grain components, and fine dust separate into different layers at the point of image measurement, or have already become separated. Said separation of the crop material flow is caused by the centrifugal forces that act on the flow of crop material. The flow of crop material must be accelerated to be conveyed out of the grain elevator and into the grain tank. The acceleration of the crop material flow out of the grain elevator causes the diverse composition of the crop material flow to become separated. Since some components of the crop material flow are lighter-weight and others are heavier, the crop material flow separates into different layers, the detection of which by the image recording unit does not allow the quality of the components of the crop material to be assessed with sufficient accuracy, because all layers are not detected in a homogeneous manner.